The broad objective of Dr. Pamela Jenkins' career development program is to improve the health outcomes of infants and children with congenital heart disease. Her current proposal concentrates on the health outcomes of infants with hypoplastic left heart syndrome (HLHS), a cardiovascular malformation whose surgical treatments still have a high mortality. The two treatment strategies, heart transplantation and staged palliation of the native heart, have different survival outcomes at five years, and previous work suggests that survival may depend in part on the pre-operative characteristics of patients with HLHS. The two surgeries may also have different functional outcomes. Such information is extremely important to parents faced with a decision between treatments. Dr. Jenkins proposes two studies to address the health outcomes of children with HLHS. The goal of the first study is to better understand which pre-operative and operative characteristics are predictors of one-year and long-term survival. In a cohort study design, characteristics will be collected for eligible patients at five participating pediatric cardiac surgical centers by medical record review. These data will be aggregated, and regression techniques will be used to generate a risk factor model to predict survival. The goal of the second study is to assess the functional health outcomes of children with HLHS, and to compare transplantation and staged surgery in terms of functional outcomes. Part 1 will utilize survey methods to assess funcitnal health outcomes for survivors of the 1989-1994 surgeries. Statistical analysis will compare the mean scores of all patients to a published norm, and compare mean scores between the two treatment groups. Part 2 is a prospective yearly collection of growth and development data, by medical record review and survey, to compare outcomes of current practice to those of 10 years ago. Analysis will compare weight and height percentiles and percentage of patients with developmental delay to those values from the previous era. Part 3 will use logistic regression to evaluate patient characteristics for their association with poor functional outcome, using the characteristics collected for mortality risk factor analysis. These studies can create a solid basis for decision-making in individual patients with HLHS, allow case-mix adjustment for centers to evaluate their outcomes, and initiate the collaboration between pediatric cardiac care teams necessary to improve outcomes for babies with HLHS.